And there are children who say they are 16, but look no older than 10, sniffing glue from bags.

These children say this "home" is their best option.

It is an option taken by 2,000 children in Romania, according to official statistics. But children's charities believe the figure is a woeful underestimate.

'A TRAGEDY'

In the economic chaos following the collapse of communism, poverty has forced many onto the street to beg, steal and survive in any way they can.

Group leader Joby, 21, says he has lived in the tunnel for nine years.

"I do not wish anyone to be in this situation," he said.

"Everyone here would like to have their own family and home. The children on the street are my family - they are my brothers."

The children sniff glue for relief from their misery

But poverty is joined by another factor. Romania is in the midst of great change and is aiming to end its reputation for neglect and abuse of children.

The large orphanages - which stand as infamous remnants of former leader Nicolai Ceausescu's era - are to be closed. International adoption has effectively been banned.

These measures must be achieved by 2007 if Romania wants to join the European Union.

The goals are admirable.

But corruption is rife and the infrastructure is shaky to non-existent in Romania. And charity workers say the measures result in many children being turned out of orphanages.

They are returning to violent homes or entering badly monitored foster care - and then ending up on the streets, charities say.

"From my point of view... it is a tragedy that we don't find the right way of doing it," said Marian Zaharia of City of Hope.

'SOLD LIKE ANIMALS'

City of Hope was set up a decade ago. It says it deals with 200 street children in this district of Bucharest alone.

Mr Zaharia estimates that 90% of children are raped on their first night - and older children use the younger ones to beg and steal for them.

They are taken in a car and sold like an animal, and used for prostitution in different houses

Marian Zaharia, charity worker

Baroness Emma Nicholson MEP defends the government's measures

But he is most concerned by the increased targeting of these children by traffickers and paedophiles.

"They are taken in a car and sold like an animal, and used for prostitution in different houses," he said.

He did not believe how bad the problem was until he discovered an illegal brothel near his sister's house.

"He had girls, starting with eight- or nine-year-olds - most of them coming up off the street," Mr Zaharia said.

Vulnerable girls

The Romanian government acknowledges the problem of child sex abuse, but it says the situation is worse in other countries.

It also says the numbers of street children are going down.

United Nations rapporteur on child prostitution and trafficking Juan Miguel Petit disagrees.

The children face the constant risks of violence and prostitution

He has just finished a two-week fact-finding tour of Romania, where he says he was shocked to find that girls were being kidnapped by force.

"Many of them were vulnerable girls who were told lies and were told they were going to France or Spain," he said.

"This is a desperate situation.

"You can imagine the future of these kids in months, weeks or even years."

He says that praise is due to the government for its efforts to reform, but he is far from convinced that the new methods of care are working.

"Romania is still in a risk situation because the basic transformations haven't happened," he said.

HUNGER PANGS

Back in the tunnel, all but one of the candles have blown out. The heat and stench of the glue used by the children is unbearable.

Toughness is all in this world - a momentary lapse can mean perpetual victimhood

Christian, 16, says the street children use this drug because it suppresses hunger pangs.

He ended up on the street after leaving an orphanage where he was beaten and forced to beg by an older gang.

"I told the directors of the orphanage, but they didn't help me because the gang gave them money and drink," he said.

Toughness is all in this world. A momentary lapse can mean perpetual victimhood.

Geena, who is 16 and dressed like a boy, lets slip that she used to get beaten up when she was first on the street. She quickly recovers herself.

"I've never been harmed. Just one time I fell over in the street, but that's just because I fainted," she said.

The Romanian government says past action to help street children has been ineffective, but there are now better co-ordinated programmes.

But what worries charities like City of Hope is that of the 36,000 children currently in orphanages, a third are due to be moved out in the next year alone to keep Romania on course in child reform.

If the infrastructure for good foster care and smaller homes is not there - and with international adoption about to be banned - they fear many more Geenas, Christians and Jobys could arrive on the street.